As the use of electronic equipment in everyday life becomes more commonplace, higher speed electronic devices become more desirable. Circuits are at the heart of electronic devices. Generally, to speed up a circuit, the speed of the signals (or their frequency) is increased. The undesirable affects associated with a signal increase as the frequency of the signal increases.
At high speed, the crossing point of an eye is critical to ensure the integrity of data stream. The ability to adjust the duty cycle/crossing point of an eye allows compensation of high speed circuit characteristic asymmetry.
Since eye crossing-point/duty cycle is critical in the design of high-speed systems, it is of utmost importance to ensure that duty cycle is measured accurately to provide an operating circuit.
Conventional solution for measuring duty cycle (especially, in high-speed differential signal, e.g., at or above 10 Gbps) is typically achieved through a potentiometer residing on an actual application board and use of external instruments such as a digital communication analyzer (DCA) or oscilloscope. This solution can, however, be cumbersome, lengthy, and unfriendly in a high volume-manufacturing (HVM) factory. Moreover, this solution requires use of costly equipment.
Accordingly, the conventional techniques fail to provide a quick, efficient, cost-effective, and user-friendly solution to measure duty cycle, which is quickly becoming a necessity when designing faster circuits.